Effect of Levy Type Load Fluctuations on the Stability of Single Machine Infinite Bus Power Systems

Abstract

In this paper, the stochastic excitations in single machine infinite bus power systems have been modeled as alpha-stable Levy processes. Through the simulations of the corresponding stochastic differential equations, we have shown that the impulsiveness and/or asymmetry in the distributions of the load fluctuations can cause the instability of the rotor angle. Hence, the synchronism is lost and the rotor angle although it is stable in the sense of probability, it might not be stable in the mean square sense. However, by properly choosing the parameters of Levy type fluctuations the rotor angle stability can be improved in the sense of probability as the beneficience of noise.